Stay strong in the challenge

Get into a press-up position, tense your abs and keep your legs and back straight. Hold in that position for 20 seconds. This is just about the best exercise you can do to enhance core strength.

More after the break

2 Side plank

Lie on your left side, with your forearm under your shoulder and feet together. Raise your hips until your body forms a straight line from ankles to shoulders. Hold for 20 seconds. Repeat on right side.

3 Crucifix press-up

Lie flat on your stomach with arms out to the sides in line with your shoulders, push up off the floor as high as you can and return slowly to your starting position. Complete six reps.

4 Athletic posture kickbacks

Start on your hands and knees. Lift your right knee off the floor and extend your left arm. Lower and repeat, switching sides. Complete six reps on each leg.

5 Clams

Lie on your side, with both knees bent and your feet in line with your back. Slowly lift your top knee in an arc, keeping your pelvis still. Complete 10 reps and then repeat on your other side.

6 Straight leg abductions

Lie on your side with legs extended and feet together. Raise your top leg, keeping your toes pointed forward. Return to start position. Repeat 10 times on each leg.